1. Field of the Invention
The present invention relates to a method and apparatus for registering a location of a portable terminal. More particularly, the present invention relates to a method and apparatus for controlling a network conversion when a portable terminal fails to register to a first network.
2. Description of the Related Art
Generally, as a mobile communication technology develops, a mobile communication network is changing generation after generation, and currently, the third generation (3G) network and the fourth generation (4G) coexist.
However, the 4G network is currently centering on providing high-speed data service, and the service area of the 4G network is at the present time overlapped with the service area of the 3G network.
Further, along with the development of such mobile communication technology, a portable terminal, which may be used in a new generation network, is being developed. More particularly, in line with the current situation that the 3G and 4G networks are operated in an overlapped form, a portable terminal, which is usable in both 3G and 4G networks, is being developed. It is possible to access respective services in different network areas through such a portable terminal, but when 4G and 3G networks are overlapped, location registration is generally tried in the 4G network first.
At this time, the portable terminal first tries location registration to be provided service in the 4G network area, and thereafter, if the location registration in the 4G network area is succeeded, the portable terminal may be provided 4G network service. In contrast, in case the portable terminal fails in location registration in the 4G network, the subscriber should be provided the 3G network service by trying location registration in the 3G network. However, the 3G network cannot know the result that the portable terminal previously failed in the location registration in the 4G network, and thus the 3G network cannot effectively provide the network conversion service of the portable terminal.
In the description below, the 4G network is called a long term evolution (“LTE”), and the 3G network is called “3G”.
For example, in case a terminal fails in the location registration in the LTE network, and succeeds in location registration in the 3G network, the terminal does not just remain in the 3G network in the overlapped area between the LTE network and the 3G network, but tries to move over to the LTE network again. In some cases, the terminal may continually try to move to the LTE network.
However, there may be various reasons in the location registration failure, and the terminal may continually fail in the location registration in the 4G network for a certain period of time, but if the terminal keeps continually trying location registration in the 4G network, the battery consumption of the terminal will greatly increase, and the service delay or disconnection may occur due to frequent connection conversion attempts. Further, in some cases, the frequent attempts will be a burden to the processor of the portable terminal which is performing multi-tasks.
Further, as the opposite situation of the above case, even when the mobile communication terminal fails in location registration while being connected to the 3G network and performing the service, if the location registration in the 4G network is tried, this attempted registration, which may be repeated over and over, may also be a problem.